diff --git a/Cargo.lock b/Cargo.lock
index 3d19a8c7..fb0bc18f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -705,6 +705,7 @@ dependencies = [
  "mime",
  "openssl",
  "percent-encoding",
+ "pkg-config",
  "serde",
  "serde_json",
  "tempfile",
diff --git a/harmonia/Cargo.toml b/harmonia/Cargo.toml
index e3b8df41..4cbaa96d 100644
--- a/harmonia/Cargo.toml
+++ b/harmonia/Cargo.toml
@@ -34,3 +34,6 @@ url = "2.4.1"
 
 
 libnixstore = { path = "../libnixstore" }
+
+[build-dependencies]
+pkg-config = "0.3"
diff --git a/harmonia/build.rs b/harmonia/build.rs
new file mode 100644
index 00000000..17cd1c15
--- /dev/null
+++ b/harmonia/build.rs
@@ -0,0 +1,3 @@
+fn main() {
+    pkg_config::probe_library("libsodium").unwrap();
+}
diff --git a/harmonia/src/narlist.rs b/harmonia/src/narlist.rs
index 0a6b38c5..c75bd399 100644
--- a/harmonia/src/narlist.rs
+++ b/harmonia/src/narlist.rs
@@ -14,6 +14,10 @@ use std::collections::HashMap;
 use std::path::PathBuf;
 use tokio::fs::symlink_metadata;
 
+fn is_false(b: &bool) -> bool {
+    !b
+}
+
 #[derive(Debug, Serialize, Deserialize, Clone, Eq, PartialEq)]
 #[serde(tag = "type")]
 enum NarEntry {
@@ -24,7 +28,8 @@ enum NarEntry {
         #[serde(rename = "narOffset")]
         nar_offset: Option<u64>,
         size: u64,
-        #[serde(default)]
+
+        #[serde(default, skip_serializing_if = "is_false")]
         executable: bool,
     },
     #[serde(rename = "symlink")]
@@ -236,7 +241,6 @@ mod test {
             .unwrap();
         let parsed_json: serde_json::Value = serde_json::from_slice(&res2.stdout).unwrap();
         let pretty_string = serde_json::to_string_pretty(&parsed_json).unwrap();
-        println!("{}", pretty_string);
         assert!(res2.status.success());
         let mut reference_json: NarEntry = serde_json::from_str(&pretty_string).unwrap();
 
@@ -244,9 +248,9 @@ mod test {
         unset_nar_offset(&mut reference_json);
 
         println!("get_nar_list:");
-        println!("{:?}", json.root);
+        println!("{}", serde_json::to_string_pretty(&json.root).unwrap());
         println!("nix nar ls --json --recursive:");
-        println!("{:?}", reference_json);
+        println!("{}", pretty_string);
         assert_eq!(json.root, reference_json);
 
         Ok(())
diff --git a/harmonia/src/signing.rs b/harmonia/src/signing.rs
index 91c6c6e5..7bb42d0f 100644
--- a/harmonia/src/signing.rs
+++ b/harmonia/src/signing.rs
@@ -10,6 +10,17 @@ use crate::config::SigningKey;
 // omitted: E O U T
 const BASE32_CHARS: &[u8] = b"0123456789abcdfghijklmnpqrsvwxyz";
 
+#[link(name = "sodium")]
+extern "C" {
+    fn crypto_sign_detached(
+        sig: *mut u8,
+        sig_len: *mut usize,
+        msg: *const u8,
+        msg_len: usize,
+        sk: *const u8,
+    ) -> i32;
+}
+
 /// Converts the given byte slice to a nix-compatible base32 encoded String.
 fn to_nix_base32(bytes: &[u8]) -> String {
     let len = (bytes.len() * 8 - 1) / 5 + 1;
@@ -127,8 +138,19 @@ pub(crate) fn fingerprint_path(
 }
 
 pub(crate) fn sign_string(sign_key: &SigningKey, msg: &str) -> String {
-    let signature = libnixstore::sign_detached(&sign_key.key, msg);
-    let base64 = general_purpose::STANDARD.encode(signature);
+    let mut signature = vec![0u8; 64]; // crypto_sign_BYTES -> 64
+    let mut signature_len: usize = 0;
+    let msg = msg.as_bytes();
+    unsafe {
+        crypto_sign_detached(
+            signature.as_mut_ptr(),
+            &mut signature_len,
+            msg.as_ptr(),
+            msg.len(),
+            sign_key.key.as_ptr(),
+        )
+    };
+    let base64 = general_purpose::STANDARD.encode(&signature[..signature_len]);
     format!("{}:{}", sign_key.name, base64)
 }
 
diff --git a/libnixstore/README.md b/libnixstore/README.md
index e7519268..86e9e042 100644
--- a/libnixstore/README.md
+++ b/libnixstore/README.md
@@ -1,16 +1,12 @@
 # libnixstore
 
-Is a library that provides simple access to your local nix store, based on c++
-bindings. It mimics the already available perl bindings but also adds bindings
-on top, that might be useful.
+These are libnix bindings required by harmonia to communicate with the local nix daemon.
+Over time we will replace the dependencies on libnix with rust-native code.
 
 Note: This project provides bindings, this makes the project automatically unsafe.
 
 Supported nix version:
-- nix 2.8
-- nix 2.9
-- nix 2.10
-- nix 2.11
+- nix 2.24
 
 ## Requirements
 
@@ -26,7 +22,6 @@ stdenv.mkDerivation {
     # required
     nix
     nlohmann_json
-    libsodium
     boost
 
     # additional packages you might need
diff --git a/libnixstore/build.rs b/libnixstore/build.rs
index d3bf01d8..668cc5b9 100644
--- a/libnixstore/build.rs
+++ b/libnixstore/build.rs
@@ -5,7 +5,6 @@ fn main() {
 
     pkg_config::probe_library("nix-store").unwrap();
     pkg_config::probe_library("nix-main").unwrap();
-    pkg_config::probe_library("libsodium").unwrap();
 
     let includedir =
         pkg_config::get_variable("nix-store", "includedir").expect("Failed to get includedir");
diff --git a/libnixstore/include/nix.h b/libnixstore/include/nix.h
index 518eeae0..814fc25f 100644
--- a/libnixstore/include/nix.h
+++ b/libnixstore/include/nix.h
@@ -10,8 +10,6 @@ rust::String query_path_hash(rust::Str path);
 InternalPathInfo query_path_info(rust::Str path, bool base32);
 rust::String query_path_from_hash_part(rust::Str hash_part);
 rust::String sign_string(rust::Str secret_key, rust::Str msg);
-rust::Vec<unsigned char>
-sign_detached(rust::Slice<const unsigned char> secret_key, rust::Str msg);
 rust::String get_store_dir();
 rust::String get_real_store_dir();
 rust::String get_build_log(rust::Str derivation_path);
diff --git a/libnixstore/src/lib.rs b/libnixstore/src/lib.rs
index 742753c1..479499fc 100644
--- a/libnixstore/src/lib.rs
+++ b/libnixstore/src/lib.rs
@@ -29,7 +29,6 @@ mod ffi {
         fn query_path_hash(path: &str) -> Result<String>;
         fn query_path_info(path: &str, base32: bool) -> Result<InternalPathInfo>;
         fn query_path_from_hash_part(hash_part: &str) -> Result<String>;
-        fn sign_detached(secret_key: &[u8], msg: &str) -> Vec<u8>;
         fn get_store_dir() -> String;
         fn get_real_store_dir() -> String;
         fn get_build_log(derivation_path: &str) -> Result<String>;
@@ -129,12 +128,6 @@ pub fn query_path_from_hash_part(hash_part: &str) -> Option<String> {
     }
 }
 
-#[inline]
-/// Return a detached signature of the given string.
-pub fn sign_detached(secret_key: &[u8], msg: &str) -> Vec<u8> {
-    ffi::sign_detached(secret_key, msg)
-}
-
 #[inline]
 #[must_use]
 /// Returns the path to the directory where nix store sources and derived files.
diff --git a/libnixstore/src/nix.cpp b/libnixstore/src/nix.cpp
index 9c2134e3..818e56df 100644
--- a/libnixstore/src/nix.cpp
+++ b/libnixstore/src/nix.cpp
@@ -14,7 +14,6 @@
 #include <nix/nar-accessor.hh>
 
 #include <nlohmann/json.hpp>
-#include <sodium.h>
 
 #include <stdlib.h>
 
@@ -127,22 +126,6 @@ rust::String query_path_from_hash_part(rust::Str hash_part) {
       get_store()->queryPathFromHashPart(STRING_VIEW(hash_part)));
 }
 
-rust::Vec<unsigned char>
-sign_detached(rust::Slice<const unsigned char> secret_key, rust::Str msg) {
-  rust::Vec<unsigned char> sig;
-  sig.reserve(crypto_sign_BYTES);
-  unsigned long long sigLen;
-  for (size_t i = 0; i < crypto_sign_BYTES; i++) {
-    sig.push_back(0);
-  }
-
-  crypto_sign_detached(sig.data(), &sigLen, (unsigned char *)msg.data(),
-                       msg.size(), (unsigned char *)secret_key.data());
-  sig.truncate(sigLen);
-
-  return sig;
-}
-
 rust::String get_store_dir() {
   return nix::settings.nixStore;
 }
diff --git a/tests/lib.nix b/tests/lib.nix
index d079b5b6..5af62976 100644
--- a/tests/lib.nix
+++ b/tests/lib.nix
@@ -3,14 +3,11 @@ test:
   pkgs ? import <nixpkgs> { },
   ...
 }@args:
-let
-  inherit (pkgs) lib;
-  nixos-lib = import (pkgs.path + "/nixos/lib") { };
-in
-(nixos-lib.runTest {
-  hostPkgs = pkgs;
+(pkgs.testers.runNixOSTest {
   # speed-up evaluation
-  defaults.documentation.enable = lib.mkDefault false;
+  defaults.documentation.enable = pkgs.lib.mkDefault false;
+  # Faster dhcp
+  defaults.networking.useNetworkd = pkgs.lib.mkDefault true;
   # to accept external dependencies such as disko
   node.specialArgs.inputs = args;
   imports = [ test ];
diff --git a/tests/t00-simple.nix b/tests/t00-simple.nix
index 7644b911..3cc9feaa 100644
--- a/tests/t00-simple.nix
+++ b/tests/t00-simple.nix
@@ -45,7 +45,7 @@
         import json
         start_all()
 
-        client01.wait_until_succeeds("curl -f http://harmonia:5000/version")
+        client01.wait_until_succeeds("timeout 1 curl -f http://harmonia:5000")
         client01.succeed("curl -f http://harmonia:5000/nix-cache-info")
 
         client01.wait_until_succeeds("nix copy --from http://harmonia:5000/ ${pkgs.hello}")
diff --git a/tests/t02-varnish.nix b/tests/t02-varnish.nix
index d68afe17..9fc40e15 100644
--- a/tests/t02-varnish.nix
+++ b/tests/t02-varnish.nix
@@ -44,7 +44,7 @@
     testScript = ''
       start_all()
 
-      client01.wait_until_succeeds("curl -f http://harmonia/version")
+      client01.wait_until_succeeds("timeout 1 curl -f http://harmonia/version")
       client01.succeed("curl -f http://harmonia/nix-cache-info")
 
       client01.wait_until_succeeds("nix copy --from http://harmonia/ ${pkgs.hello}")
diff --git a/tests/t03-chroot.nix b/tests/t03-chroot.nix
index d7ac87e5..83360276 100644
--- a/tests/t03-chroot.nix
+++ b/tests/t03-chroot.nix
@@ -42,7 +42,7 @@
       harmonia.systemctl("start harmonia-dev.service")
       harmonia.wait_for_unit("harmonia-dev.service")
 
-      client01.wait_until_succeeds("curl -f http://harmonia:5000/version")
+      client01.wait_until_succeeds("timeout 1 curl -f http://harmonia:5000/version")
       client01.succeed("curl -f http://harmonia:5000/nix-cache-info")
 
       client01.wait_until_succeeds(f"nix copy --from http://harmonia:5000/ {f}")